1. Field of the Invention
The present invention relates to an apparatus for sampling water in a borehole, which is capable of accurately collecting samples while preventing introduction of foreign substances into the borehole and capable of controlling the sampling speed by monitoring the situation of collecting samples at a target depth in the borehole, and a method thereof.
2. Background of Related Art
In general, groundwater pollution is seriously harmful to human beings, in particular, when human beings drink the polluted groundwater.
Meanwhile, a groundwater pollution source may be introduced into the groundwater from ground surface through a borehole. In addition, a pollution source, which is introduced into an underground not through the borehole, may encounter with the borehole while flowing along a stratum interface, a fault plane or a fractured zone, so that the pollution source may be introduced into the groundwater.
The pollution source described above is not introduced into the groundwater through any portions of the borehole, but introduced into the groundwater only at the positions at which the stratum interface, fault plane or fractured zone encounter with the borehole.
There is a related art for the present invention, such as Korean Unexamined Patent Publication No. 2012-0014310 (published on Feb. 17, 2012) entitled “Apparatus and method for groundwater sampling using hydraulic couplers”. In the apparatus disclosed in the related art, couplers are connected to both ends of a water sampling pipe made of a metal. In case of positioning a sampler at a target depth, a socket and a plug constituting the coupler are connected to each other to open both ends of the sampler in order to allow groundwater to freely flow in/out. Thereafter, at the target depth, the sockets or plugs are permitted to be separated from the couplers at the both ends of the water sampling pipe by using a lift device, so that the both ends of the water sampling pipe are sealed to simultaneously take groundwater samples at multiple target depths.
However, according to the apparatus and method for groundwater sampling using hydraulic couplers of the related art which can simultaneously sample groundwater at multiple target depths, it is difficult to accurately collect a sample at a target depth. In addition, it is very difficult to monitor the situation of collecting the samples. Further, it is difficult to arbitrarily control the sampling rate to control an amount of sample.
In addition, according to the apparatus and method for groundwater sampling using hydraulic couplers of the related art which can simultaneously sample groundwater at multiple target depths, a foreign substance may be introduced into the collected sample.